Those events are supposed to be unbalancing -- that's their purpose. And I found that particular event to be loads of fun.

So there

What consequences did it bring?

I had that as well in a game. A precursor artifact was found in the Vizzard system that made every planet a class 4 planet. With all the terraforming techs I got planets ranging from class 11 to class 16 (!). If that wasn't good enough, the range was 2 sectors wide. So a section of 5 x 5 sectors was suddenly filled with habitable planets. And this was a part of the galaxy filled to the brim with class 0 planets . About 150 new class 4 planets were open for colonization.

Luck for me, I have a brain. And the AI on sub-normal doesn't. I ordered all my shipyards to start building colonizers. The AI didn't (atleast not on a large scale). I went from about 40 planets to 150 in a year orso. I only stopped expanding because The Jagged Knife showed up, got 48 planets, of which 40 were mine.

So yes, it's messes up the game. If only the AI would've taken advantage of it ...

Why are you complaining when you had your advesaries set at SUB-NORMAL. Did you actually expect them to take advantage of anything at that level??? Play all of your games on Normal or Challenging and you will see how resourceful the other races can be

This has been a feature at least since Dark Avatar. I've seen even larger "planetary explosion" events than the one you describe. They provide a big shake up to the game, but what you saw is functioning as intended. I don't like them because my preferred game-style is for a map with rare habitable planets.

To be honest, managing all those planets would piss me off so much I'd just build a Terror Star and have at.

When I play at sub normal, some of the AIs have veritable fleets of colony ships waiting in the wings. I'd be surprised if they didn't send anything out.

Hell, they're like roaches, they pop up in every little class 1 that I missed.

i back in late DL and early DA i got this event a couple times, but never in my own area of the map. i haven't really seen in happen lately.

in each case, i was still able to colonize most of the new planets before the AI was even close. that's my only real complaint about this event, is that the AI doesn't seem to change its production focus accordingly (or at least quickly enough). otherwise i think it's a great event.

You know you can turn off events like that don't you?

This event and others like it are intended to seriously upset the power balance of the galaxy, and 5-10 planets is not enough to do that (in most cases).

I love those events, especially when they are in another civ's territory. It really causes the territory of the map to change quickly, and the industry and influence power can quickly help you take down other civs.

but again, this isn't a mega event but rather a generic event. re-loading would obviously un-do it, but i'm replying for a different reason. i'm not sure, but i think the non-mega events aren't entirely random. it seems like this event only occurs in the space of a weak empire, similar to the precursor artifact event that slowly boosts their ability bonuses. hard to confirm this, however.

it could be that the event triggered around the minor race, though that would be surpremely stupid.